NEW GARRISON CARRIAGES. 
339 
II .—The Blatform , 
(Allowing a recoil of 6 ft.)* 
The platform is similar in general construction to that for the 12-in. 
M.L.F. gun of 25 tons. 
The sides are 15| ft. long and 24 ins. in greatest depth. They are 
connected by four transoms, two bottom plates, and two truck plates. 
The trucks (13 ins. in diameter in front and 18 ins. in rear), are 
secured on their axles, each by a collar, and pin. They are placed 10 ft. 
apart, and set to radii of 10 ft. 2 ins. and 20 ft. 2 ins. The front trucks 
are of steel. 
The front bottom plate is slotted, to give access to the nuts between 
the first and second transoms. 
The front truck plate is set down, to clear the buffer bracket of the 
carriage; the second transom being extended down to meet it. 
The hydraulic buffer is special ; its piston-rod 3 ins. in diameter. It 
is secured on the platform in the usual manner. 
The platform is fitted with rack traversing and chain (Scott's) 
running-back gear, worked by the same winch handles, similar to that 
already in use in the navy. 
The traversing gear is as follows:—A short longitudinal shaft (a, 
Fig. III.) is placed under the rear of the platform, having a bevel 
metal pinion, A, upon its front, and another, B, upon its rear extremity. 
The former gears into a cast-iron horizontal rack fixed upon the floor 
of the casemate, and the latter into the bevel part of a metal clutch 
double pinion, C, carried upon a cross shaft, b, under the platform. 
The shaft has upon each extremity, inside the side of the platform, a 
spur wheel, B, into which a pinion, F, carried upon a spindle passing 
through the side, gears. The spindle has upon its outer extremity a 
spur wheel, F, which is driven by a pinion, G, with winch handle, T. 
The gain of power in traversing is 44*15 : 1. 
The running-back gear consists of two endless chains, one on either 
side of the platform, inside, passing over sprocket wheels, H, II, the 
front wheel secured in an adjusting fork, by which the tension of the 
chain can be regulated, and the rear fixed on a cross shaft, c , lying a 
little to the front of the cross shaft of the traversing gear. This shaft 
has a spur wheel, K, upon it, into which the spur portion of the clutch 
double pinion of the traversing arrangement gears, the bevel portion 
being thrown out of gear with the pinion of the traversing shaft. The 
clutch is moved, as desired, to work either the traversing or running- 
back gear, by a lever handle, X, at the left rear of the platform, which 
is secured by a keep pin. The gain of power for running back is 
86*5:1. 
Proposed Experimental Fittings oe the Platform for the 
38-ton Gun. 
It is proposed to fit, experimentally, a casemate platform as follows :— 
1. The trucks to be 4^ ins. instead of 3 ins. wide on the sole, in 
* Platforms allowing a recoil of 7 ft. are also to be made. 
